1. Field of the Invention
The present invention relates to a data projector apparatus, and particularly to a data projector apparatus in which a temperature rise at a front panel is suppressed.
2. Description of the Background Art
A projector apparatus is one of apparatuses for projecting images and the like on a screen. In a projector apparatus, light emitted from a light source is projected onto a screen. The light source includes, for example, a mercury lamp, a metal hydride lamp, a xenon lamp, or the like.
The light source becomes hot during illumination. Thus, the light source needs to be cooled. In order to cool the light source, for example, a projector apparatus described in Japanese Patent Laying-Open No. 2002-214703 is provided with a feed port 116 and a feed fan 117 on the bottom of a housing 120, as shown in FIG. 10. On the other hand, an exhaust port 118 and an exhaust fan 119 are provided on the rear surface of housing 120.
Feed fan 117 takes outside air from outside feed port 116 into housing 120 thereby to cool a light source 102 and the like.
In a projector apparatus 101 described in Japanese Patent Laying-Open No. 2000-35614, for example, a heat sink 130 is attached to a light source 102, and a cooling fan 131 is installed in the vicinity of light source 102, as shown in FIG. 11.
Cooling air is taken in while being sucked through cooling fan 131 thereby to cool light source 102 and heat sink 130.
Recently, a data projector apparatus for displaying visual information such as digital images based on digital signal processing has been proposed as a projector apparatus.
As shown in FIG. 12, in a data projector apparatus 101, light emitted from light source 102 passes through a color filter 102b to enter a prescribed device 104. This device 104 is a spatial light modulator in which mirrors 104a as high-speed digital optical switches corresponding to pixels in number are formed on a semiconductor chip.
Light that has entered device 104 is reflected by mirror 104a and changed in direction, for example, by approximately 90° with respect to the emitted direction. The redirected light is transmitted through a lens 114 to be projected on a screen (not shown).
In this manner, in data projector apparatus 101, light emitted from light source 102 is reflected by the prescribed device 104 to be projected onto the screen.
Now, it is required to bring light source 102, device 104 and lens 114 closer together to shorten an optical path from light source 102 to lens 114 in order to reduce the size of data projector apparatus 101 and to eliminate an effect in the middle of the optical path.
In order to do so, light source 102 and device 104 are arranged closer to front panel 110 provided with lens 114. Because of the arrangement of light source 102 and device 104 at the side of front panel 110, a board part 106 for processing signals is inevitably arranged to the rear side with respect to front panel 110.
Here, if air is supplied from light source 102 toward board part 106 in order to cool light source 102, the air warmed by light source 102 flows toward board part 106 and then possibly affects signal processing and the like in board part 106.
On the other hand, if air is supplied from light source 102 toward device 104, the control and the like on mirror 104a in device 104 may be affected by the air warmed by light source 102. On the contrary, if air is supplied from device 104 toward light source 102, the lateral width of housing 120 is increased.
Therefore, in order to cool light source 102, the air should be supplied from substrate 106 toward light source 102. A fan 108 for feeding air toward light source 102 is arranged, for example, between board part 106 and light source 102. In this case, an air intake port 116 is provided on the side or rear face of housing 120.
The air taken in from air intake port 116 and blown onto light source 102 by fan 108 is then delivered from front panel 110 to the outside of housing 120. Here, a relatively large opening cannot be provided at front panel 110 so as to prevent leakage of light from light source 102. In addition, provision of a large opening at front panel 110 is not preferable in view of the design.
Therefore, the air passes through a small gap (not shown) at front panel 110 and then exits outside housing 120. At that time, the air warmed by heat from light source 102 directly contacts front panel 110, and therefore the temperature of front panel 110 rises to approximately 100° C.
An approach for preventing a temperature rise at front panel 110 is disclosed, for example, in Japanese Patent Laying-Open No. 2001-330818, wherein a tape member having a high thermal conductivity is adhered on a portion where the temperature rises, and the heat of the member is dissipated.
However, this approach is disadvantageous in that the heat is conducted through the tape member thereby to excessively increase the temperature at that part of front panel 110 which is located around the tape member.